Cooling jackets, such as water jackets, are used in engines to remove heat from the engine assembly and provide cooling to various engine components. Therefore, the likelihood of thermal degradation of the engine block and the components coupled thereto may be reduced. Moreover, the cooling jackets may enable the combustion chamber to be maintained at a desirable operating temperature or within a desirable operating temperature range, thereby increasing combustion efficiency. Cooling jackets may be integrated into both the cylinder head and/or the cylinder block to facilitate temperature regulation in different sections of the engine.
U.S. Pat. No. 5,745,993 discloses an engine having a water jacket integrated into a cylinder head. Water is flowed through the water jacket in the cylinder head as well as a water jacket in the cylinder block to remove heat from the engine generated during combustion. The water jacket includes a first passage positioned below an exhaust port and adjacent to an exhaust valve seat as well as a second passage positioned adjacent to another portion of the exhaust valve seat and the intake valve. As a result, uneven cooling of the valve seat may occur, thereby warping the valve seat. Warping of the valve seat may cause the valve to only partially seal the combustion chamber, thereby degrading combustion operation. In particular, gases may flow out of the combustion chamber during compression, and/or power strokes, thereby decreasing combustion efficiency.
Therefore, in one approach, an engine cylinder head is provided. The engine cylinder head includes a portion of a first combustion chamber, an upper coolant jacket portion, and a lower coolant jacket portion directing heat from the first combustion chamber and including a first coolant passage and a second coolant passage, the first coolant passage and the second coolant passage laying along a lateral axis, at least a portion of the first coolant passage separated from the second coolant passage via first and second walls.
When the aforementioned cylinder head is utilized, the likelihood of valve seat warping may be reduced while at the same time providing cooling to the cylinder head and specifically the exhaust manifold. Consequently, warping of the valve seat may be avoided while maintaining the cylinder head within a desired operating temperature. Therefore, the combustion chamber may be operated within a desirable temperature range, increasing combustion efficiency without negatively affecting the shape of the cylinder head and specifically the valve seat via warping.
The above advantages, and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings. For example, while the examples provided herein show axial displacement of the jacket portion, rotational displacement (or combinations of axial and rotational displacement) may also be used.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.